html {
    height: 100%;
  }
  
  html body {
    height: 100%;
    background-image: url(../img/beijing.png);
    background-size: cover;
    position: relative;
  }
  
.box {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 25%;
    height: 60%;
    border-radius: 10px;
    transform: translate(-50%, -50%);
    background-color: rgba(256, 256, 256, 0.5);

  }
  
.box form input{
    height: 30px;
    width: 150px;
    font-size: 14px;
    border-radius: 10px;
    padding-left: 10px;
    outline: none;
    border: solid 1px rgb(85, 236, 121); 
    

  }
.control {
    margin: 20px 0;
    text-align: center;
    
  }
.control input[type='submit'] {
    color: #fff;
    background-color: cornflowerblue;
    border-color: rgb(112, 154, 233);
    width: 20%;
  }
#gly{
    width: 10px;
    height: 10px;
    
  }
#yh{
    width: 10px;
    height: 10px;
  }
  p{
    color: cornflowerblue;
    font-size: 20px;
    text-align: center;
  }
  #js{
    margin-left: -50px;
  }